Oxidative stress during aging of Saccharomyces cerevisiae in stationary culture was documented by demonstration of progressive increase in the formation of superoxide, decrease in the content of acid-soluble thiols and of acid-soluble antioxidant capacity of cell extracts, and accumulation of aldehydes and protein carbonyl groups in two yeast strains and decreases in activities of antioxidant enzymes. Cells of a CuZn-SOD (superoxide dismutase)-1-deficient strain showed a higher loss of viability than cells of an isogenic wild-type strain. Cell survival was augmented, and changes in biochemical parameters were ameliorated, by addition of exogenous antioxidants (ascorbic acid, glutathione and melatonin) in both strains.

Pesticides, used in culture, may induce oxidative stress by stimulation of free radicals production, what may result in lipid peroxidation, proteome damage, changes in DNA and RNA structures and disturbance of total antioxidative capacity in organisms’ cells. In disturbances caused by increase synthesis ROS (reactive oxygen species) or lack antioxidative defense that is in oxidative stress it is seen one of all causes of aging process. Chronological aging of baker’s and wine yeast Saccharomyces cerevisiae in liquid stationary culture is used as model of research on the aging process. As a result of aging changes take place in yeast cells which have physiological, genetic, metabolic and morphological character, what cause their death in consequence. Some scientists treat chronological yeast aging as analogy of fibroblasts aging of multicellular organisms, skeletal muscles or nerve cells. The aim of the experiment was to obtain the answer on question connected with toxicity effect two widely available pesticides in shape of trade preparation, used among other things in culture of grapevine Miedzian 50 WP (Cu 50WP) and Siarkol Extra 80 WP (S 80WP) on vitality of wine yeast in chronological aging. During research cells of wine yeast Tokay, which are used in production of white wines, and cells of Malaga strain, used in production of white and red wines, were applied. Yeast culture with pesticides supplementation in determined concentrations was conducted through seven days in YPG medium. At that time vitality of yeast cells was determined by the percentage of cells surviving, percentage of dead cells and culture density. Considerable influence on decreasing vitality of yeast cells in the process of aging showed S 80WP, what correlate with the increase of applied concentration in both example of Malaga and Tokay. Obtained results in application of Cu 50WP indicated lower toxicity in culture of both studied strains in comparison to the control. Our studies suggest that studied pesticides may cause the intensity of processes connected with cells aging.

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The aim of conducted research was to determine in what degree inoculation of soil by fungi Trichoderma modifies process of phytoavailability of cadmium through roots and above ground parts of maize (Zea mays) and how it affects cadmium activity as damaging factor of photosynthetic apparatus of plants. Outline of vase experiment covered 5 objects (control without addition of cadmium and 4 objects with increasing amount of cadmium in amount from 10 to 80 mg.kg-1 d.m. soil), and within each object two variants: soil without (-T) and with (+T) addition of fungi of Trichoderma (+T) in shape of granulated preparation of Trianum–G in amount of 750 g.m-3 soil. Increasing amount of cadmium in surface caused decrease of harvest size of roots and above ground parts of maize, but inoculation of surface by Trichoderma fungi softened those changes. Amount of cadmium in plants was increasing promotionally to increasing amount of that metal in soil, but the presence of fungi of Trichoderma type caused decrease of phytoavailability cadmium by above ground parts of maize. Decrease parameters of chlorophyll fluorescence F0, FM, Fv, Fv/FM Fv/F0 showed lack of disturbances in photosynthetic apparatus of maize despite decrease the amount of chlorophyll in leaves under the influence of inserted cadmium doses to soil.